This invention relates to safety wheels for vehicle use which are capable of supporting the vehicle in a manner such as to enable it to continue to travel safely without any trouble even upon failure of the tire air pressure as resulting from tire puncture.
Generally, in the event that the air sealed in a tire is lost due to puncture or any other tire failure during travel of the vehicle particularly to an express highway or a crowded road, tire replacement on the spot must be extraordinarily dangerous and in some cases practically impossible. Accordingly, it is highly desirable to enable the vehicle safely to continue to travel even upon the tire failure, as it enables the driver to send the vehicle at once to any of the nearest repair shops without going to the trouble of tire replacement. Obviously, this means a great convenience to the driver even in cases where the traffic condition allows tire replacement on the road.
Accordingly, developments of a safety wheel that makes it possible to drive the vehicle even in the event of tire puncture safely to a repair or other suitable place with a minimum of damage to the tire punctured have been in demand and various forms of safety wheel have previously been proposed in which a flat protector is built in the tire to support the vehicle upon tire puncture in place of the lost tire air pressure thereby to enable the vehicle to safely continue to travel. In this connection, it is desirable that the flat protector once built in the tire exhibit a rigidity as high as possible in order to efficiently serve the intended function of supporting the vehicle in place of the tire air pressure lost when the tire is punctured. On the other hand, it is desired that the flat protector, a unit to be built in the tire, be made itself to exhibit only a rather limited rigidity in order to facilitate its assembling into the tire. In the past, however, there has been no form of flat protector proposed that can satisfactorily meet both of these two requirements.